Lock for Fire Hydrants

ABSTRACT

A lock for fire hydrants includes a stem with an activating end ( 2 ), which at the top projects through a fixedly mounted top cover ( 1 ), said fire hydrant including a weathershield ( 7 ) to be mounted on the activating end ( 2 ). The lock includes a fastening means ( 5 ) adapted to be fixedly mounted atop the top cover ( 1 ) adjacent the activating end ( 2 ) of the stem. Further, a locking device ( 16 ) is provided for locking the weathershield ( 7 ) together with the fastening means ( 5 ).

The invention relates to a lock for fire hydrants and the like liquid discharge outlets, where the lock includes a stem with an activating end, which at the top projects through a fixedly mounted top cover, said fire hydrant including a weathershield to be mounted on the activating end.

Previously the fire hydrants were conventionally structured so as to be easy to use because the safety measures were to be quickly removed in order to allow a quick access to water for extinguishing the fires. However, the fire hydrants are often coupled to the public water system, and accordingly it is of vital importance that the safety level is high so as to prohibit stray vandalists or persons intending to damage the water system from using the fire hydrant or a similar liquid discharge outlet.

The object of the invention is therefore to provide a lock which in a simple and inexpensive manner ensures the necessary safety against unauthorised use of the hydrant at the same time as said hydrant can be taken into use in a relatively easy manner, if necessary.

The above object is according to the invention accomplished by the lock including a fastening means adapted to be fixedly mounted on the top cover adjacent the activating end of the stem, and by a locking device being provided for locking the weathershield together with said fastening means.

As a result it is not sufficient that the user merely screws off the weathershield, but he or she must also open the locking device in order to remove or release said weathershield and in order to obtain access to the activating end of the stem on the fire hydrant. If desired, the locking device and consequently the weathershield can be removed or released by means of special purpose tools, such as a tool for cutting or splitting said locking device into two parts.

According to the invention the fastening means may be adapted to be mounted adjacent the activating end of the stem and be covered by the weathershield in the mounted state thereof with the result that said fastening means is exceptionally well protected against unauthorised attempts at removing it.

In addition, the fastening means and the weathershield may according to the invention include mutually matching openings which allow the locking device to be used in form of a padlock. In this manner the locking device is of a particularly simple type which can be removed by means of a key.

When the top cover is associated with a thrust nut including a through hole allowing passage of the activating end of the stem, the fastening means may according to the invention advantageously include a recess for receiving at least a portion of said thrust nut. As a result, the mounting of the fastening means can be stabilized by the thrust nut.

The invention is described in greater detail below with reference to the FIGURE of the accompanying drawing. This FIGURE is a perspective view of the top cover for a fire hydrant and including the lock according to the invention, where the individual parts have been spaced apart for the sake of clarity.

The top cover shown in the FIGURE is designated the reference numeral 1 and is a top cover of a conventionally known type used for an existing type of fire hydrants. The top cover 1 forms part of the external housing of the fire hydrant and protects the uppermost end of said fire hydrant while allowing passage of an uppermost activating end 2 of a stem. The stem renders it possible to open or close the valve of the fire hydrant. Usually, the uppermost activating end 2 is a separate member fixedly connected to the stem and retained on said stem by means of a thrust nut 3. The thrust nut 3 includes a central through opening 4 allowing passage of the activating end 2.

According to the invention, the lock includes an integrally cast fastening means 5 with a recess 6. When seen in the mounted state, the recess 6 is downwardly defined by a wall 7 with a through hole 8 for receiving a bolt 9. The bolt 9 is adapted to co-operate with a threaded bore (not shown) in the top cover 1 in such a manner that the fastening means 5 can be fastened to the top cover 1 by means of said bolt 9.

The fastening means 6 is shaped such that it allows both a turning of the activating end 2 and a mounting of a weathershield 7. The weathershield 7 is of a conventionally known type and is adapted to be mounted atop the top cover 1 by means of a bolt 18. The bolt 18 is screwed fixedly into a central, threaded hole 19 in the top of the activating end 2. In the top, the weathershield 7 includes an activating top adapted to receive at least a portion of the activating end 2. Internally, the activating top 10 is shaped such that internally it matches the cross section of the activating end 2 and externally such that the stem of the fire hydrant can be activated through the activating end 2 by a turning of the weathershield 7 by means of a suitable key adapted to engage the activating top 10. Alternatively, the weathershield can be removed and the activating top be engaged directly by the key.

The fastening means 5 includes a through hole, and the axis 12 of said hole in the mounted state of said fastening means 5 extends in a plane perpendicular to the axis of rotation 13 of the activating end 2. As illustrated in the drawing, the hole 12 is interrupted by the recess 6 of the fastening means 5. The weathershield 7 includes two holes 14 and 15 positioned in such a manner that in the mounted state thereof and with the activating end 2 in the closing position, they are aligned with the through hole in the fastening means 5. As a result a suitable padlock 16 can be fastened through the two holes 14 and 15 of the weathershield 7 and the through hole 11 of the fastening means 5. Upon mounting of the padlock 16, said padlock 16 can be locked in a conventionally known manner and only be removed by means of a key or a suitable cutting or splitting up tool.

On the side of the fastening means 5 opposite the recess 6, said fastening means 5 can include a recess matching a portion of the thrust nut 3 in such a manner that the resulting mounting of the fastening means 5 on the top cover 1 is particularly stable.

The fastening means 5 can be made of any suitable material, such as stainless steel, and in the illustrated embodiment the fastening means 5 is completely hidden by the weathershield 7 in the mounted state. Therefore, unauthorised persons cannot remove the mounting bolt 9 without removing the padlock 16 and the weathershield 17 first.

The invention has been described with reference to a preferred embodiment. Many modifications can be carried out without thereby deviating from the scope of the invention. In the mounted state the fastening means must be fixedly connected to the housing of the fire hydrant, but said fastening means 5 can also be placed outside the weathershield 7 provided the demounting thereof is impossible unless the padlock 16 or another suitable locking device has been removed first. The locking device 16 is a padlock, cf. above, but other locking devices can, of course, also be used provided they require special purpose tools or keys for their removal. 

1. A lock for fire hydrants and the like liquid discharge outlets, where the lock includes a stem with an activating end (2), which at the top projects through a fixedly mounted top cover (1), said fire hydrant including a weathershield (7) to be mounted on the activating end (2), characterised in that the lock includes a fastening means (5) adapted to be fixedly mounted atop the top cover (1) adjacent the activating end (2) of the stem, and that a locking device (16) is provided for locking the weathershield (7) together with the fastening means (5).
 2. A lock according to claim 1, characterised in that the fastening means (5) is adapted to be mounted adjacent the activating end (2) of the stem and be covered by the weathershield (7) in the mounted state thereof.
 3. A lock according to claim 1 or 2, characterised in that the fastening means (5) and the weathershield (7) include matching holes (11, 14, 15) allowing a padlock to be used as locking device (16).
 4. A lock according to claim 1, and where a thrust nut (3) is associated with the top cover (1), said thrust nut including a hole (4) for the passage of the activating end (2) of the stem, characterised in that the fastening means (5) includes a recess for receiving at least a portion of the thrust nut (3). 